Ok, that's just not right. Your site took 2 minutes, 15 seconds to load on my dialup connection. Frankly, I think the site needs to be re-built from the ground up, but that's for another thread.
Ok, as for your question, here's what I'd do.
Use the H1 element to describe what the page is about. This will go at the top of your document (note: for the purposes of this post, the word document will refer to everything between the <body> and </body> tags). Then in each major section of your site (your sidebars, and main content area, for example), use a H2 to describe and mark up those sections. Then, inside your main content area, where you have your articles, use a H3 for your article titles.
You'll still have a lot to do, but at least it would be a start.